SEOUL, Sept 11 (Reuters) - GS Caltex, South Korea’s second-largest oil refiner, said on Monday that it was unsure when it would be able to restart a hydrocracker and aromatics unit after they were hit by fire last month.

The refiner in August experienced two fires at its Yeosu refinery, southwest of Seoul, shutting its 66,000 barrels-per-day (bpd) vacuum residue hydrocracker (VRHCR) and one of its petrochemical units.

“We are not sure of the timing, but we will resume operations when it’s deemed safe,” a company spokesman said.

The 790,000-bpd facility will be able to keep churning out enough oil for domestic demand, but its exports may be crimped slightly, the spokesman added.

GS Caltex is equally owned by GS Energy Corp, a unit of GS Holdings and U.S. oil major Chevron Corp. (Reporting by Jane Chung; Editing by Joseph Radford)